2005 Prius "Problem" message, No engine, NEW Coolant Pump, blown fuse, and Inverter

Here goes.

A couple of months ago we were driving down the freeway when the car stalled and went into limp mode.
We pulled over ( barely coasted into a parking lot ) and were unable to re-start it, it would not read "ready" or go into neutral.
Had it towed home. ( For free, as a kindness from a local body shop owner. )

The coolant pump fuse had blown.
Replaced it.

Then replaced the coolant pump.

Then as a Summer project, replaced the entire Hybrid Inverter just in case. ( Fun, learned a lot. )

All the while, no codes are being given via our OBD2 reader.

Today we finished re-installing the Inverter and tried to start up the car.
Accessories work, and there is turbulence in the Inverter coolant tank.

However, on the display flashes the word Problem! and then the red car with the exclamation symbol comes on.
On the dash appears the Red Triangle, the engine light, ABS, and the slippery road icon.
"Ready" still has not appeared, and I can only shift into Neutral or Park.
There is no idling from the engine, the engine is silent.

We noticed today that a fair amount of water had gotten into the ignition coil well, so our next step is going to be to replace those, and check the spark plugs.

I also noticed that there is no "KEY" button to toggle on-off the smart key, which is a concern because I have read that this is needed in order to do the reboot sequence.
I have even tried "clearing" the non-existent codes, which of course did nothing.

We tried jump starting just in case, no change.
Filled the tank with gas, no change.
We even checked the gas cap thinking it was something super dumb and easy to overlook - nope.

Again, there are no codes, so we've been flying blind this whole time, going purely off of symptoms.
Towing the car or taking it to a dealer is not an option as we are living paycheck to paycheck.
We will keep replacing parts until we cannot anymore, but I am starting to worry that this could be a less enjoyable issue, perhaps something with the engine itself.

Any advice is much appreciated, as I sorely miss my independence.

I have been documenting these repairs, and can upload photos if needed.

 

Oh!
It also has a new hybrid battery.
However, I've noticed that when trying to start the car it reads as a 3/4 full battery, then quickly drops to one red bar.
And the power button light ( start button ) is red, so right after I post here I will be messaging the vendor as it is still under warranty.
At least then we can cross that off.

 

178,000 miles.

13.6v for the reading.

The gaps between restart attempts were:
A few minutes ( at first ).
A few hours after the tow home.
Two weeks later when the coolant pump arrived and was installed.
One month later, when the Inverter arrived.
One week later ( today ), after the Inverter was pulled and the new Inverter was installed.

I have pulled codes from this reader before for things like the 12v battery, hybrid battery, oil pressure, and brakes, but am more than happy to invest in reliable Prius aware brand reader that the folks here can rep.
If Techstream works on Chromebook I would gladly go down that route as well.

Thank you, I have lurked for a long time, and have reached my limit as far as going it alone.

 

I now see that 13.6v may be inaccurate as it was charging at the time.
It is a fairly new battery ( 6 months ), but I will test it again to have an accurate reading.
I don't fully suspect it though as all accessories and displays are working properly.
Will update when the next step has been taken.